Sling immobilisation compared with surgery in the management of adults with a displaced fracture of the distal clavicle (DIDACT): a multi-centre, pragmatic, parallel group, non-inferiority, randomised controlled trial

Background Fractures of the clavicle, which primarily occur in young males, constitute 2.6–5% of all fractures in adults. Distal clavicle fractures account for 20-25% of all clavicle fractures. These are treated with an operation, involving fracture fixation, or with sling immobilisation. Patients operated on may have a reduced risk of the fracture not healing (non-union) and may lead to quicker recovery. However, they are at risk of complication; (estimated at 48%) including infection, plate breakage and refracture after metal removal. Upper limb support with a sling, typically between 2 and 4 weeks, restricts activity whilst providing comfort during the early painful stages of healing. The risk of non-union with a sling can be up to 35-40% but appears to cause minimal functional deficits in most individuals. If a non-union occurs, and surgical intervention is indicated, it can prolong the treatment period and increase costs. Using HES data for 2019 and HRG codes the cost to the NHS of surgical fixation in this fracture population is around £6 million per annum. At a time when the NHS is under more pressure than ever with the impact of COVID-19, it is important to answer the question of whether a cheaper, safe and non-surgical option can replace more costly and invasive surgery. Aim To determine whether self-reported functional outcome, measured by the Disability of Arm, Shoulder and Hand (DASH) at one year, following sling immobilisation is not inferior to surgical fixation in adults with a displaced fracture of the distal clavicle and whether this is a cost-effective treatment option. Methods A two-arm, pragmatic, multi-centre, randomised, non-inferiority trial with parallel groups, allocated on a 1:1 ratio and stratified by age (<65 or =65 years). It includes a 12 month internal pilot and a full health economic analysis. The target population is adults with a radiological diagnosis of a displaced fracture of the distal clavicle that does not involve the acromioclavicular joint. The setting will be Major Trauma Centres and Trauma Units within the United Kingdom. Patients will be identified either in the Emergency Department or Fracture Clinic and will attend for routine out-patient appointment at 6 weeks, 3 and 12 months. Data will also be collected at 6 months. We need data from 170 participants at 12 months to provide 90% statistical power to establish noninferiority of sling immobilisation compared with surgical fixation within a margin of 10 points on DASH based on the upper limit of a 95% two-sided confidence interval. Assuming 20% attrition, gives a total target sample size of 214. Timelines for delivery The study will be 50 months duration: 6 months set up; 12 months internal pilot; 14 months main trial recruitment; 12 months follow-up; 6 months data cleaning, analysis and reporting. Anticipated impact and dissemination The trial will improve decision making about the management of adults with a displaced fracture of the distal clavicle. Targets for dissemination will include NICE, Integrated Care Systems, Department of Health and Social Care and the Speciality Advisory Committee (for the curriculum for clinicians who do these surgical procedures). Results will be presented at professional meetings and published in high impact journals. A summary of results will be developed in plain English, as well as an infographic and animation for patient focused outlets with advice from our Patient/Public Advisory Group.